The player running the army in the campaign is the CinC player for the entire battle. He may consult the other players or not, but all decisions about the army's deployment and orders ultimately rest with him.
It is assumed that each army will be roughly twice the size of standard DBA army. Campaign effects may increase, decrease, or change the composition, but armies using these rules should have no more than 36 and no fewer than 15 elements.
Before the battle, the CinCs of each side divide their armies into commands, choose and set up the terrain, and either personally deploy or direct the deployment of the figures on the table.
Treat unwalled BUAs as bad going that blocks line of sight and ranged fire, like a wood or orchard. They have no other defensive value or characteristics.
Treat walled BUAs as camps (especially if being used as a camp), but with a variable defensive value depending on the type of fortications:
+2 if built up, such as reinforced ditches, fences, walls, and hedges, improvised barricades of furniture, dirt and brush, palisades, or other prepared defenses such as might be erected in a few hours or days.
+3 if a well-built and designed wall of stone, wood, or faced earth, the type typically found surrounding motte-and-bailey castles, or many ancient and medieval minor towns and fortified villages.
+4 if a fully fortified castle or city, with carefully designed and heavily built walls, towers, and gates, lined with ramparts and battlements and easily manned and defended by a small number of fighters, and only carried with great difficulty by overwhelming numbers after a great deal of preparation and/or a long siege.
BUAs should never be bigger than a camp, unless you are playing out a carefully-balanced scenario involving an assault on or sally from a walled city or castle.
Ignore all rules about denizens. If your BUA is not acting as one side's camp, and the residents must be depicted, treat them as Hordes.
Comments? Questions? Mail your input to Ix (fathom at armory dot com).